1. Field of the Invention
The present invention relates to orthopedic surgical instruments and more particularly a soft tissue anchor delivery apparatus for inserting a soft tissue anchor into a patient's joint tissue (for example, glenoid) to effect a soft tissue repair. Even more particularly, the present invention relates to an improved soft tissue anchor delivery system that comprises an instrument body that includes a plurality of gripper fingers mounted on the distal end of a tube and configured such that when held in a closed position they form a support under the enlarged head of a soft tissue anchor, the gripping fingers being contained about the soft tissue anchor using an actuating tube that slides over the combination of the fingers, soft tissue anchor, and a pushrod and wherein the pusher is spring loaded as to allow the pusher to be driven distally upon retraction of the actuating tube, driving the anchor free of the deployed fingers into a surgically formed opening.
2. General Background
Small soft tissue anchors and small tissue repair tacks are used to repair certain bodily tissues. As part of a surgical repair procedure, a surgeon uses a K-wire to drill through a first section of soft tissue that is to be attached to a second section of tissue (for example, the glenoid). The K-wire drills through both the tissue to be attached and the glenoid using a K-wire. The surgeon over drills the K-wire through the soft tissue and into the middle of the glenoid forming a surgical opening for receiving the soft tissue anchor. This procedure allows the surgeon to place an anchor into the surgically formed opening. Tissue anchors and repair tacks usually include an elongated hollow shank, and an enlarged head, and an expansion or actuating pin that enters a longitudinal bore of the shank and head. When the actuating pin enters the bore, it spreads the shank creating a tight fit with the surrounding tissue at the surgically formed opening.
A number of patents have issued for soft tissue anchors and repair tacks used for treating and repairing torn bodily material in vivo. For example, U.S. Pat. No. 4,924,865 "REPAIR TACK FOR BODILY TISSUE" discloses an apparatus for repairing in-vivo torn cartilaginous or other bodily tissue during a surgical procedure. The '865 patent employs a repair tack of bio-degradable material chosen to have a degradation time in excess of the required healing time for the tissue. The repair tack has a shaft or shank portion with a longitudinal bore and a grip or enlarged head portion adapted for releasable engagement by an applicator instrument. In one embodiment, the grip portion of the tack is a cross bar at the proximal end of the shank or shaft which fits into an open sided slot at the forward end of the applicator. U.S. Pat. No. 4,924,865 is incorporated herein by reference.
Another patent that relates to repair tacks and a method of joining torn parts of bodily tissue in vivo is U.S. Pat. No. 4,895,148. The '148 patent discloses a method for repairing in vivo torn cartilaginous or other bodily tissue, particularly torn meniscus tissue, during arthroscopic surgery. The '148 patent employs a repair tack of biodegradable material chosen to have a degradation time in excess of the required healing time for the tissue. The repair tack has a shaft portion with a longitudinal bore and a grip portion adapted for releasable engagement by a hollow applicator. In one embodiment the grip portion of the tack is a cross bar, at the proximal end of the shaft, which fits into an open-sided slot at the forward end of the applicator. A needle passes through the hollow applicator and tack bore to project from the distal end of the tack shaft. With the tack supported in the slot and the needle passing through the stem, the needle and tack can be inserted into the joint cavity through a portal in the skin or through an insertion cannula. The sharpened needle point is placed in contact with the torn tissue and force is applied to the holder and the needle to cause the needle and the tack to penetrate the tissue to a desired depth. The point of the needle is withdrawn into the axial opening of the applicator and the cross bar is displaced from the slot, thereby leaving the tack firmly secured in the tissue. U.S. Pat. No. 4,495,148 is incorporated herein by reference.
An applicator for treating torn bodily material in-vivo is disclosed in U.S. Pat. No. 4,884,572 entitled "TACK AND APPLICATOR FOR TREATING TORN BODILY MATERIAL IN VIVO". The '572 patent discloses an apparatus for repairing in-vivo torn torn cartilaginous or other bodily tissue, particularly torn meniscus tissue during arthroscopic surgery, employs a repair tack of biodegradable material chosen to have a degradation time in excess of the required healing time for the tissue. The repair tack has a shaft portion with a longitudinal bore and a grip portion adapted for releasable engagement by a hollow applicator. In one embodiment the grip portion of the tack is a cross bar, at the proximal end of the shaft, which fits into an open-sided slot at the forward end of the applicator. A needle passes through the hollow applicator and tack bore to project from the distal end of the tack shaft. U.S. Pat. No. 4,884,572 is incorporated herein by reference.
Most prior art instruments for placing and inserting repair tacks and soft tissue anchors are awkward to use and inefficient. The present invention provides an improvement to prior art methods and apparatus for delivery of soft tissue anchors.